Yet Another Crossfire Question... ramp-up?

So I've been playing Kingdoms of Amalur lately and with a pair of 6950 2GB's at x16/x16 they each run about 50%-60% load pegging me out at 120FPS (vSync). The other day I started one of the expansion packs (Teeth of Naros) and noticed that my FPS was taking a serious hit, like down in the 40-70FPS ranges. What bothered me about this is that my GPU's were still sitting at their 50%-60% load instead of ramping up to compensate. Is this a glitch that can be worked around or a common problem? Do I have something set wrong? Shouldn't my cards be speeding up?

It's not uncommon for the engine itself to be the limiting factor, sometimes it just runs out of threads and becomes locked to just one or two threads, other times its own timing routines don't let it go any faster.

It's not uncommon for the engine itself to be the limiting factor, sometimes it just runs out of threads and becomes locked to just one or two threads, other times its own timing routines don't let it go any faster.

I doubt it's the CPU (Phenom II x6 @ 3.2Ghz) or the engine as it only happens in the Naros expansion so far. The rest of the game world holds a steady 120FPS.

That's a pretty slow CPU. In games, it's identical to my Phenom II X4 955BE if I were to ever run it at stock, because games just don't give a shit for your six cores (or my four).

And I see a linear gain from putting more MHz on the CPU. I'm going out on a limb here and thinking that the Naros whatever is more detailed or has more things going on, so is a heavier load, which your 3.2 GHz chip just can't handle.

Go somewhere. Stand still. Note your framerate. Put a few hundred MHz on your CPU or take it off. Do the same again, same place. Get three datapoints of CPU clocks and see if they trace out a line.

Another theory is that the 50% is really telling you that only 1 card is working at 100%, so CF isn't supported. That's a guess though and doesn't explain why the load isn't just on one card in the reading.

Phenom II's haven't been the shit since ever gaming-wise. They were competitive up until the faster Core 2 Quads started showing up almost 3 years ago. The X6 models extended the life a bit and I think it took Sandy Bridge to pass that one in Jan of 09.

Someone correct me if I'm wrong though, I might be off a bit on some of those.

What I'm seeing is that the CPU isn't taxing hardly at all, but the GPUs aren't really spinning up either, hanging in around 60% usage and only getting about 45-60 FPS in Naros, where they're working a little harder (65%-75%) in the normal realm and hanging in at about 150-180FPS steady.

I'm still confused as to why the GPUs aren't kicking up to 90% or so to bring the FPS up higher. The cards both have the headroom to do it, but its not happening. What else should I check into?

And as for SB, they came out in March of 2011, in fact the announcement that the B3 chipsets were shipping came out (literally) 3 days after I built this machine... FRAK YOU INTEL!! FRAK YOU AND YOUR "Coming Soon" BULLSHMUK!!!

There shouldn't be any "ramp-up"; once the 3D kicks in, the cards should be immediately operating as fast as they can. The only things that will reduce framerate are a general system bottleneck (your CPU), or Crossfire not actually working.

There shouldn't be any "ramp-up"; once the 3D kicks in, the cards should be immediately operating as fast as they can. The only things that will reduce framerate are a general system bottleneck (your CPU), or Crossfire not actually working.

My understanding was that the GPU's would only run as hard as they needed to hit the desired frame rate. Turning the vSync off Should have kicked both cards up to 100% the whole time, but they never kicked up to that. Obviously, by the fact that both cards are running at 60%-80%, the crossfire is working or I would see 1 GPU at 100% and the other at 0% like I've seen on other games that weren't using the crossfire. Am I understanding the theory correctly?

The CPU's were overclocking a bit since the stock speed is 3.2Ghz and I had a few cores hitting 3.3+ (TurboCore seems to work a little) but manually kicking up the clocks made no noticeable difference in the frame rates and the CPU usage wasn't really affected on any of the cores that I could see with my monitor windows open.

Is it maybe an AMD driver issue? It's only a DX9 game and has been out for a couple Catalyst revisions now. I do have RadeonPro helping out the crossfire, would the settings list for the game help, maybe tweaking the RP profile?

It's definitely playable, it's just bugging me why it's 1: not running at full speed on both cards and 2: taking the hit and not ramping up to compensate. Know what I mean?

Believe me, if I were a rich man, I'd be dropping this setup in favor of a S2011 i7 with a pair of nVidia cards, but I didn't have the option at the time and the die was pretty much cast when the whole SB fiasco happened.

So, what else should I try to track this issue down? I appreciate the help guys.

Your GPU clockspeeds are apparently 840Mhz, and the 6950 is supposed to run at 800Mhz; the brand you have probably has a mild overclock built-in, or the drivers are doing it. Are you sure those "usage" figures aren't something like fan speed ? Your GPUs do indeed appear to be running at full speed either way.

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My understanding was that the GPU's would only run as hard as they needed to hit the desired frame rate.

I don't think that's right; as far as *I* understand it, the "target framerate" for a video card is always "as fast as possible". It's probably just a CPU bottlenek as suggested so far.

Do you have another game you can try of the same era to see how it behaves?

I had a typo above, SB was jan of 11. I rocked mine since then and didn't bother replacing with b3 on one system. Not really a point, the bug was so obscure.

Yeah, unfortunately for me I was at sea until mid Feb of that year and everything SB had been pulled by the time I came home. All the news sites said the fix was "Coming Soon" and I waited... and waited.. and waited... and when my next deployment was looming close and DA:2 had already dropped (which was the focus of the upgrade in the first place) I had to bite the bullet and go AMD. After I got all the parts in, put it together, installed everything, got it all stabilized, it was less than 72 hours later that the announcement was made that the SB motherboards and chips were on their way and should be available by the end of the week. FFFRRRAAKKK!!!

Yeah... that's why I'm running an AMD setup.

The only other comparable games I have would be DA:2 if I run it in DX9 mode and maybe Witcher 2 if I can get it to run in DX9 mode. Which should I go check out for more data points?

ChrisG wrote:

Your GPU clockspeeds are apparently 840Mhz, and the 6950 is supposed to run at 800Mhz; the brand you have probably has a mild overclock built-in, or the drivers are doing it. Are you sure those "usage" figures aren't something like fan speed ? Your GPUs do indeed appear to be running at full speed either way.

Yup, I have a mild OC (via AMD's overdrive) on both cards to bring them in line with each other since they're different brands. The core clock is stable, I'm looking at the GPU1 and GPU2 usage in Afterburner and don't have the fan speed info loading on them. CPU usage is viewed through the AMD Overdrive CPU Status monitor app. Looking at the CPU usage, I'm not thinking it's a CPU bottleneck because so many of the cores are running at a lower percentage even considering the TurboCore kicking in.

They're doing 840Mhz, up from whatever their desktop idling speed is. This is why it all smacks of a CPU bottleneck. You have an overhead in the GPU setup - i.e. they're running flat-out with whatever the CPU can give them - which isn't enough.

They're doing 840Mhz, up from whatever their desktop idling speed is. This is why it all smacks of a CPU bottleneck. You have an overhead in the GPU setup - i.e. they're running flat-out with whatever the CPU can give them - which isn't enough.

Aaahhh... OK, that makes sense. So the reason the GPU's are at 75% isn't because they don't need to work that hard, but because they can't get the data through the CPU fast enough to process it. In essence, the GPU's are out performing the CPU. Right?

Well krap, here's to hoping that Piledriver solves the issue or that I win the lotto and can move to a S2011 setup.

Are there any tweaks (short of turning down the graphics options) that might help? I'll try to push my CPU and see what that does, but I've never had much luck for some reason even with the large ass heat sink and good cooling.

I'm seeing a slight difference with the 200Mhz and 400Mhz bumps in Naros, still not fully loading up the GPU's though, so I guess it really is a CPU bottleneck... bummer...

The Witcher 2 is surprising at how much it just beats the crap out of my cards! Wow, both cards cranked up and I still can't keep a steady 40FPS. Now if I could figure out how to get DA:2 to use the crossfire I'd be set.

So... anyone want to hand over next weeks winning lottery numbers so I can get a S2011 i7 setup?